Polymer-based mass analysers

We have designed, simulated fabricated and tested a miniature quadrupole mass filter (QMF) with hyperbolic electrodes for high resolution mass scanning [1]. Our hyperbolic QMF was fabricated at the University of Liverpool using low-cost rapid prototyping (RP) digital light processing (DLP) technique. Compared to other RP techniques, such as selective laser melting and selective laser ablation, DLP offers significantly smaller feature size that allows a higher degree of accuracy. It also has the potential to produce fully integrated mass spectrometers with a single mass analyser or with an array of analysers.

DLP QMF prototype with r0 = 2 mm and electrode length of 50 mm.

Experimental optimisation of H2 mass peak obtained from the DLP QMF.

Using DLP, we have also implemented a linear ion trap (LIT) mass analyser with hyperbolic electrodes for high mass range applications [2]. Ion traps in general are the only mass analysers that are capable of tandem mass spectrometry (MS/MS) with a single analyser, which increases their analytical capabilities. Furthermore, ion traps operate at higher pressure, which renders them smaller and more portable than other MS systems.

DLP LIT prototype with r0 = 2.5 mm and electrode length of 40 mm.

Experimental mass spectrum of 5 ppm mixture of cocaine and methamphetamine obtained from the DLP LIT.‌

References

1. B. Brkić, N. France, A. T. Clare, C. J. Sutcliffe, P. R. Chalker and S. Taylor, Development of quadrupole mass spectrometers using rapid prototyping, J. Am. Soc. Mass Spectrom. 20, (7), pp. 1359-1365 (2009). PDF
2. A. T. Clare, L. Gao, B. Brkić, P. R. Chalker and S. Taylor, Linear ion trap fabricated using rapid manufacturing technology, J. Am. Soc. Mass Spectrom. 21, (2), pp. 317-322 (2010). PDF


Acknowledgement
The ERA foundation and EPSRC are acknowledged for their financial support of this work via the Follow-On-Fund.